Hypotension, if uncorrected, is life-threatening and occurs as the result of various underlying conditions such as trauma, septic shock or drug reactions. The first line of treatment is intravenous fluids, and if this fails to correct the hypotension then vasopressors are deployed. The first line vasopressor is a catecholamine infusion. Catecholamines are amines derived from the amino acid tyrosine, and they include epinephrine (adrenaline), norepinephrine (noradrenaline), phenylephrine, and dopamine, which act as both hormones and neurotransmitters that increase blood pressure. While largely effective at treating hypotension, some patients fail to respond to adequate doses and are defined as catecholamine-resistant. These patients frequently have a high mortality and no acceptable alternatives.
The use of high doses of catecholamines in patients with severe hypotension is associated with poor outcomes. For example, the in-patient, 90-day mortality rate is 50-93% for patients who require norepinephrine as a vasopressor at doses that exceed 0.1 μg/kg/min, and 94% of patients who require norepinephrine at doses above 100 μg/min die.
Thus, alternate methods of regulating blood pressure in patients with catecholamine-resistant hypotension are needed.